Before Joaquin Phoenix met his fiance Rooney Mara and they had their son, he dated around like any other celebrity. One of his first public relationships was with Liv Tyler after they met on the set of Inventing the Abbotts and they became one of the most iconic 90s couples ever.

They probably bonded over the fact that they were both raised in very interesting circumstances. Tyler is the daughter of Aerosmith's lead singer, Steven Tyler, but she didn't know it until she was 11, having been raised to think that another rocker, Todd Rundgren was her father. Phoenix, on the other hand, grew up a child actor with the rest of his siblings and narrowly escaped a cult with the family.

Phoenix and Tyler might be settling down with their own families now, but there was once a time when they could have had their own together. Here's the truth about their relationship.

Meeting On Set And Falling In Love...Secretly

Sometimes, when celebrities meet their co-stars for the first time it can be love at first sight. When you know you know, right? Tyler apparently had this ability to find her soulmate quite quickly when she met Phoenix.

"I fell in love with Joaquin the second I saw him," Tyler told The Morning Call the year the film came out. "It just happened immediately."

Related: The Reason Casey Affleck And Joaquin Phoenix Went From Friends To Enemies

Phoenix said at the time that he didn't even know that she was a rockstar's daughter.

"For the first screen test that we did, I didn't really know anything about her (Tyler)," said Phoenix. "I had heard her name. I'm not really hip to magazines or those television shows where they talk about actors. The only thing I had seen was a shampoo commercial which she did."

It didn't take long into filming for the pair to start secretly dating, and they kept it as private as possible. They even came up with sneaky ways of avoiding being caught.

"[Joaquin] would sit at the other end of the makeup trailer and say, 'Oh, my God, [Liv’s] such a babe,' and talk to the makeup girl," Tyler explained the ruse they played. "It would be like, 'I could never get her,' and she believed him."

Despite having to keep it a secret, Tyler was not afraid of going through with her relationship with Phoenix. Their romance is what she'd dreamed of her whole life, and she wasn't going to allow anything to come between it.

"Every other relationship I have ever had -- looking back at my diaries ... It was like, one day I was in love and this person was the only other person on the face of the Earth. And then the next day they were never written about again," Tyler explained.

Related: 20 Little Known Facts About Liv Tyler’s Relationship With Her Dad, Steven Tyler

"With him (Phoenix), I just knew. And I didn't feel threatened or afraid of the idea to get involved with him when we were working. I just kind of knew and hoped and prayed that I would love him forever. And that's all I could do. And it's lasted."

Phoenix was just happy to find an equal of sorts, but he's a man of few words anyway.

"What I felt about Liv (Tyler) was that I have a new friend, a really great friend," Phoenix said. "I was just immediately moved by her honesty. We sat between takes and just talked."

When asked about whether or not he'd act with Tyler again, Phoenix gave a less than enthusiastic reply. "I'm not going to do a film just to be in it with her," he said.

Tyler, who probably showed more love towards him, said she'd love to be co-stars again.

Things Didn't Go Anywhere...Fast

A year after Inventing the Abbotts came out, they split amicably after they realized their romance was going nowhere. They were together for three years.

"I’m a great believer in people coming into your life, and you into theirs, for a reason. And I know that when Liv and I met, it was for a reason — I really needed her and she really needed me," Phoenix explained the breakup to Cosmopolitan in 1999.

"And at a certain point, I think we stopped evolving with each other, stopped progressing, and made a very mature decision to move on, even though there was still a great love there. There’s no one gossipy thing that I can share. I’m thankful that we had the time we had."

But splitting amicably allowed for them to remain friends to this day. In 2015, Tyler attended Prada's benefit for The Lunchbox Fund, an organization that gives school meals to children in South Africa, and which both Phoenix and his sister Rain are board members.

Related: Was Joaquin Phoenix Close To His Brother River Phoenix?

Attending the event was in no way awkward for Tyler.

"I'm friends with all my exes! I love them so much! I guess it depends on what happens, right? I consider Joaquin and all of his sisters to be like family," Tyler told Elle at the event hosted by her ex.

"We were so young when we were together, like 18 to 21. He was my first love. So he's a huge part of even my sense of humor. Like, Milo will say something and I'll say, 'Wow, that's something that Rain said! That's something Joaquin said!' Because they were such a big part of those years when you're just starting out on your own. I have so much love for that family. I learned a lot from them."

With all the relationship drama in Hollywood nowadays, it's a breath of fresh air to hear of a celebrity couple who split on good terms and are able to still be friends. But this is Tyler and Phoenix. They're class acts who can party as exes for a good cause. They practically invented how exes should act with each other.

Next: Joaquin Phoenix Almost Landed Batman… Here’s Why It Didn’t Happen